Early clinical signs in lysosomal diseases.

BACKGROUND AND AIM: The lysosomal storage diseases are a group of monogenic diseases with multisystemic impairment and chronic progression induced by the deficiency of lysosomal acid hydrolases involved in the breakdown of various macromolecules. The accumulation occurs in the macrophages of the reticule-endothelial system and causes enlargement and functional impairment. The mainly involved organs are the brain, liver, spleen, bones, joints, airways, lungs, and heart. The aim of this study was to evaluate early symptoms, signs and the delay in the diagnosis of different lysosomal diseases. METHODS: The medical documentation of 188 patients with lysosomal storage disorders, aged 1-70 years, were analyzed. All these patients were specifically diagnosed, by enzyme and molecular assay. RESULTS: The age of clinical signs onset varies in different type of lysosomal diseases, from the first months of life or early childhood in severe form, to adulthood in attenuated forms. The delay between the clinical signs onset and specific diagnosis ranged from 0.5 months to 57.91 years. CONCLUSIONS: The lysosomal storage diseases are rare diseases with childhood onset, but these early signs and symptoms are not recognized and are often taken into account when the vital organs damage becomes manifest.

Gene variants of osteoprotegerin, estrogen-, calcitonin- and vitamin D-receptor genes and serum markers of bone metabolism in patients with Gaucher disease type 1.

PURPOSE: Osteopathy/osteoporosis in Gaucher disease type 1 (GD1) shows variable responses to enzyme replacement therapy (ERT); the pathogenesis is incompletely understood. We aimed to investigate the effects of several gene variants on bone mineral density (BMD) and serum markers of bone metabolism in GD1. PATIENTS AND METHODS: Fifty adult Caucasian patients with GD1/117 controls were genotyped for gene variants in the osteoprotegerin (TNFRSF11B; OPG), estrogen receptor alpha, calcitonin receptor (CALCR), and vitamin D receptor (VDR) genes. In patients and 50 matched healthy controls, we assessed clinical data, serum markers of bone metabolism, and subclinical inflammation. BMD was measured for the first time before/during ERT (median 6.7 years). RESULTS: Forty-two percent of patients were splenectomized. ERT led to variable improvements in BMD. Distribution of gene variants was comparable between patients/controls. The AA genotype (c.1024+283G>A gene variant; VDR gene) was associated with lower Z scores before ERT vs GA (P=0.033), was encountered in 82.3% of patients with osteoporosis and was more frequent in patients with pathological fractures. Z score increases during ERT were higher in patients with the CC genotype (c.9C>G variant, TNFRSF11B; OPG gene; P=0.003) compared with GC (P=0.003). The CC genotype (c.1340T>C variant, CALCR gene) was associated with higher Z scores before ERT than the TT genotype (P=0.041) and was absent in osteoporosis. Osteocalcin and OPG were lower in patients vs controls; beta crosslaps, interleukin-6, and ferritin were higher. CONCLUSIONS: We suggest for the first time a protective role against osteoporosis in GD1 patients for the CC genotype of the c.9C>G gene variant in the TNFRSFB11 (OPG) gene and for the CC genotype of the c.1340T>C gene variant (CALCR gene), while the AA genotype of the c.1024+283G>A gene variant in the VDR gene appears as a risk factor for lower BMDs. Serum markers suggest decreased osteosynthesis, reduced inhibition of osteoclast activation, increased bone resorption, and subclinical inflammation during ERT.

Modelling long-term evolution of chitotriosidase in non-neuronopathic Gaucher disease.

Chitotriosidase, an enzyme secreted by activated macrophages, is widely used as a biomarker for therapeutic monitoring and patient follow-up in Gaucher disease (GD), a lysosomal disorder caused by an inherited deficiency of glucocerebrosidase. We analyzed the long-term evolution of chitotriosidase aiming to establish an accurate model that describes the influence of enzyme replacement therapy (ERT) and the impact of several covariates. A total of 55 patients with non-neuronopathic (type 1) GD were followed for almost 17 years (during a maximum of 7.57 and 8.96 years, before and after the onset of ERT, respectively). Plasma chitotriosidase activity, measured yearly before the onset of ERT and at 6-month intervals after the initiation of ERT, was analyzed as a function of several covariates (age at diagnosis and at ERT initiation, nature of the most frequent genotypes, spleen status and the occurrence of bone complications). The evolution of chitotriosidase was approximated by a sigmoidal function, which allows the calculation of predicted values, based on several parameters inferred from our data. Splenectomy and the occurrence of bone complications significantly delayed the decline in chitotriosidase activity and induced higher mean residual values after long-term (4-9 years) ERT. Likewise, patients who started ERT infusions under 15 years of age had significantly higher mean residual chitotriosidase activities. The influence of other covariates did not reach statistical significance. In conclusion, we propose a novel model describing the evolution of chitotriosidase, allowing more accurate treatment adjustments, according to the variations of this biomarker.

Clinical and Genetic Characteristics of Romanian Patients with Mucopolysaccharidosis Type II.

BACKGROUND: Mucopolysaccharidosis type II (MPS II, Hunter syndrome) is a rare X-linked disorder caused by deficiency of iduronate-2-sulfatase (I2S) enzyme, which leads to the accumulation of partially digested glycosaminoglycans (GAGs) in the lysosomes and induces multisystemic alteration (coarse facial features; skeletal dysplasia; hepatosplenomegaly; joint stiffness and contractures; heart, lung, vision, and hearing disability; profound neurological decline).The purpose of this study is to present the clinical and genetic characteristics of Romanian patients with Hunter syndrome and the genotype-phenotype correlation. MATERIAL AND METHODS: 15 unrelated patients, with MPS II ranging from mild (4 subjects) to severe phenotype (11 subjects) aged 2 to 20 years, were evaluated clinically, cognitive development, enzyme assay and molecular analysis. RESULTS: The molecular analysis of the 15 unrelated Romanian MPS II patients has identified 15 different mutations (2 major genetic defects (13%) and 13 minor genetic defects (87%)): microdeletions and point mutations (missense, nonsense), seven of them described for the first time-deletion encompassing 3 to exon 7; c823G>T, pD275Y; c.1600A>C (pN534H); c.102_10delAG (p.D5Cfs*11); c.448_471del (p.P150_P157del); c.421delA (p.I141Yfs*72); and c.419-1G>C. The major genetic defects were correlated with a severe course of disease. CONCLUSION: This is the first study on the clinical and molecular characterization of the MPS II Romanian patients. This study supports the evidence of the mutational heterogeneity of the I2S gene as well as the difficulty to correlate genotype and phenotype in the patients with MPS II.

Cholelithiasis in Patients with Gaucher Disease type 1: Risk Factors and the Role of ABCG5/ABCG8 Gene Variants.

BACKGROUND AND AIM: Patients with Gaucher disease type 1 (GD1) show an altered lipid profile and a certain degree of insulin resistance, which might contribute to cholelithiasis (CL) and could possibly be associated with ABCG5/ABCG8 gene variants. We aimed to investigate the prevalence of CL in Caucasian adult patients with GD1 and the possible risk factors, including gene variants of the ABCG5/ABCG8 genes. METHODS: 61 Caucasian patients with GD1 (38 female/23male), aged 18-62 years and 61 healthy subjects matched for age, gender and BMI, without CL, for comparison of lipid profiles. Data before start of enzyme replacement therapy (ERT) were recorded: clinical, haematological, severity parameters, splenectomy, genotype. Fasting lipid profiles before ERT, glycemia, insulinaemia, HOMA-IR at the last visit were documented. Genotyping for the gene variants D19H, Y54C, T400K, A632V (ABCG8); Q604E (ABCG5) was performed. RESULTS: CL occurred in 45.9% of patients. Risk factors were: age, family history of CL, higher BMI values, LDL-cholesterol (LDL-C), disease severity, splenectomy. A specific dyslipidemia was found in patients vs. controls. Total serum cholesterol (TC) and LDL-C were higher in patients with CL than in those without; no obvious influence of insulin-resistance to lithogenesis was found. Patients with the GG genotype of D19H and the CC genotype of T400K (ABCG8 gene) had significantly higher levels of TC and LDL-C. CONCLUSION: Patients with GD1 showed an increased prevalence of CL, which was associated with common and disease-specific risk factors. Starting ERT soon after clinical onset and avoiding splenectomy might reduce the risk of CL in GD1.

Ultrasonographic evaluation of the median nerve at the level of the carpal tunnel outlet and mid forearm in patients with type II Mucopolysaccharidosis.

AIMS: The ultrasonographic (US) evaluation of the median nerve at the level of the carpal tunnel outlet (CTO) and mid forearm in pediatric patients with mucopolysaccharidosis type II (MPS II) and comparison with healthy subjects. MATERIAL AND METHOD: Fifteen children with MPS II and 44 healthy children were included in the study and they were divided into three age groups. The cross-sectional area, the appearance of the nerve, and the ratio of the cross-sectional areas were evaluated by US. RESULTS: At the level of the CTO the mean area of the nerve was increased in all MPS II groups compared with the correspondent healthy age groups and the differences were statistically significant (p<0.01). At the level of the mid forearm the differences were statistically significant only for the first age group. Other US findings at the level of the CTO in the MPS II groups were represented by hypoechogenicity (86.67 % on the right and 93.33% on the left), thickened fascicles (80% bilaterally), irregular contour (53.33% bilaterally) and the presence of the Doppler signal including the nerve (26.67 % on the right and 33.33 % on the left). The CTO/mid forearm cross-sectional area ratio was higher in all MPS II age groups and the differences were statistically significant (p<0.001). CONCLUSION: In patients with MPS II there are significant US changes in the size and aspect of the median nerve.

Evaluation of neopterin as a biomarker for the monitoring of Gaucher disease patients.

OBJECTIVES: Biomarker research is an important area of investigation in Gaucher disease, caused by an inherited deficiency of a lysosomal enzyme, glucocerebrosidase. We evaluated the usefulness of neopterin, as a novel biomarker reflecting chronic inflammation and immune system activation in Gaucher disease and analysed its evolution in response to enzyme replacement therapy (ERT). METHODS: Circulating plasma neopterin levels in 31 patients with non-neuronopathic Gaucher disease were measured before and after the onset of ERT and were compared with those of 18 healthy controls. Plasma chitotriosidase activity was also monitored, as a reference biomarker, against which we evaluated the evolution of neopterin. RESULTS: Neopterin levels were significantly increased in treatment-naïve patients (mean 11.90 ± 5.82 nM) compared with controls (6.63 ± 5.59 nM, Mann-Whitney U test P = 0.001), but returned to normal levels (6.92 ± 4.66 nM) following ERT. Investigating the diagnostic value of neopterin by receiver operating characteristic analysis, we found a cut-off value of 7.613 nM that corresponds to an area under the curve of 0.780 and indicates a good discrimination capacity, with a sensitivity of 0.774 and a specificity of 0.778. DISCUSSION: Our results suggest that measurement of circulating neopterin may be considered as a novel test for the confirmation of diagnosis and monitoring of the efficacy of therapeutic intervention in Gaucher disease. Plasma neopterin levels reflect the global accumulation and activation of Gaucher cells and the extent of chronic immune activation in this disorder. CONCLUSION: Neopterin may be an alternative storage cell biomarker in Gaucher disease, especially in chitotriosidase-deficient patients.

Problems in the Diagnosis of Cyclic Vomiting Syndrome in Children.

The cyclic vomiting syndrome (CVS) is an infrequent condition in pediatric practice, in which recurrent vomiting episodes are followed by asymptomatic periods. The authors report the case of an 8-year and 2-month old child who had been hospitalized on several occasions for persistent vomiting accompanied by nausea, and periumbilical and epigastric abdominal pain. The child's anamnesis and clinical examination determined the doctors to suspect aCVS, which was later confirmed due toruling out all of the differential diagnoses: infectious, drug-related or surgical causes. CVS is a severe condition, which causes nutrition disorders, social integration problems, school absenteeism and lower life quality on the whole. This condition requires early detection in order to initiate adequate supportive therapy, to identify the triggering causes and to prevent them.

Advanced model-based control studies for the induction and maintenance of intravenous anaesthesia.

This paper describes strategies toward model-based automation of intravenous anaesthesia employing advanced control techniques. In particular, based on a detailed compartmental mathematical model featuring pharmacokinetic and pharmacodynamics information, two alternative model predictive control strategies are presented: a model predictive control strategy, based on online optimization, the extended predictive self-adaptive control and a multiparametric control strategy based on offline optimization, the multiparametric model predictive control. The multiparametric features to account for the effect of nonlinearity and the impact of estimation are also described. The control strategies are tested on a set of 12 virtually generated patient models for the regulation of the depth of anaesthesia by means of the bispectral index (BIS) using Propofol as the administrated anaesthetic. The simulations show fast response, suitability of dose, and robustness to induce and maintain the desired BIS setpoint.

Lessons learned from closed loops in engineering: towards a multivariable approach regulating depth of anaesthesia.

In this paper is presented a brief state of art regarding the multivariable formulation for controlling the depth of anaesthesia by means of two intravenously administrated drugs, i.e. propofol and remifentanil. In a feasibility study of determining a suitable variable to quantify analgesia levels in patients undergoing cardiac surgery, the bispectral index and an electromyogram-based surrogate variable are proposed as the controlled variables. The study is carried on in the context of implementing a multivariable predictive control algorithm. The simulation results show that such a paradigm is feasible, although it does not guarantee perfect knowledge of the analgesia level-in other words, the variable is not validated against typical evaluations of the pain levels (e.g. clinical scores).

Osteoarthropathy in mucopolysaccharidosis type II.

INTRODUCTION: Mucopolysaccharidosis type II (MPS type II, Hunter syndrome) is a rare (~ 1/1500.000), X-linked inherited disorder (affects boys) due to deficiency of the lysosomal enzyme iduronate sulfatase (Xq.28). The complex clinical picture includes osteoarthropathy with a tendency to flexion stiffness and disability. In our country, the specific diagnosis and enzyme replacement therapy (ERT), are recently available in the Center for Genetic Pathology Cluj. OBJECTIVES: Assessment of clinical features, radiological and imaging of osteoarthropathy in MPS type II and their evolution under ERT. MATERIAL AND METHODS: The study included 9 male patients with a suggestive clinical picture of MPS type II; the diagnosis was confirmed by enzymatic assay and the patients were treated with ERT. Osteoarthropathy was assessed before treatment: a) clinical tests (joint goniometry, walking test) and b) radiology (X-rays of the hand and wrist, spine and pelvis), bone densitometry in five patients. Clinical tests were repeated after therapy. RESULTS: Chronic osteoarthropathy was present in all patients. Joint mobility was reduced with quasi stationary trend after 12 months of treatment. The walking test was improved after treatment. Radiological assessment revealed: hand bones changes, delayed bone age, vertebral changes, pelvis changes, kipho-scoliosis and aseptic necrosis of the femoral head in 100%, 88%, 88%, 55% and 11% respectively. Bone mineral density was normal in five of the nine patients evaluated. CONCLUSIONS: Chronic osteoarthropathy with flexion stiffness is an essential component of the clinical picture of MPS type II. ERT allows an improvement/arrest of evolution (depending on disease severity and time of initiating therapy).

Dynamic changes of lipid profile in Romanian patients with Gaucher disease type 1 under enzyme replacement therapy: a prospective study.

BACKGROUND: Dyslipidemia in Gaucher disease includes reduced total, low-density lipoprotein (LDL)-, and high-density lipoprotein (HDL)-cholesterol (C). No prospective analysis of lipid profile changes in treatment-naïve patients under enzyme replacement therapy (ERT) is available. METHODS: We analyzed lipid profile changes during ERT in a prospective controlled manner. Twelve treatment-naïve patients, Gaucher disease type 1 (GD1), 29.5 ± 12.9 years, 4M/8F. Diagnosis was made by enzymatic measurement and mutational analysis. Total-, LDL-, and HDL-C, triglycerides (TG), and LDL subfractions were assessed before the start of ERT with imiglucerase and biannually for 3 years. Patients were matched with healthy controls before and after 3 years of ERT. RESULTS: At baseline, we found severely reduced HDL-C concentrations (23.6 ± 5.4 mg/dl) and enhanced LDL/HDL ratios (3.1 ± 0.7). HDL-C increased after 6 months (29.2 ± 5.7, p = 0.023), LDL/HDL ratio decreased after 30 months (2.5 ± 0.5, p = 0.039). TG, even not consistently enhanced at baseline (128 ± 31.3 mg/dl), yet higher than in controls (p < 0.001), decreased after 18 months, being comparable with controls after 3 years of ERT. Small, dense LDL (mg/dl) increased continuously without significant difference to controls. After 3 years of ERT, only reduced HDL-C concentrations persisted as a potentially atherogenic alteration; however, mean concentrations markedly improved (42.9 ± 8.3 mg/dl, p < 0.001). Lipid parameters correlated with six markers of disease severity. CONCLUSIONS: This is the first prospective controlled study regarding lipid profile dynamics during ERT (glucocerebrosidase) in initially treatment-naïve GD1 patients. The most important changes were reduced HDL-C and enhanced LDL/HDL ratio. Their dynamics during ERT and correlations with markers of disease activity suggest that they can be considered markers of disease severity and follow-up in Gaucher patients under treatment.

Revised recommendations for the management of Gaucher disease in children.

UNLABELLED: Gaucher disease is an inherited pan-ethnic disorder that commonly begins in childhood and is caused by deficient activity of the lysosomal enzyme glucocerebrosidase. Two major phenotypes are recognized: non-neuropathic (type 1) and neuropathic (types 2 and 3). Symptomatic children are severely affected and manifest growth retardation, delayed puberty, early-onset osteopenia, significant splenomegaly, hepatomegaly, thrombocytopenia, anemia, severe bone pain, acute bone crises, and fractures. Symptomatic children with types 1 or 3 should receive enzyme replacement therapy, which will prevent debilitating and often irreversible disease progression and allow those with non-neuropathic disease to lead normal healthy lives. Children should be monitored every 6 months (physical exam including growth, spleen and liver volume, neurologic exam, hematologic indices) and have one to two yearly skeletal assessments (bone density and imaging, preferably with magnetic resonance, of lumbar vertebrae and lower limbs), with specialized cardiovascular monitoring for some type 3 patients. Response to treatment will determine the frequency of monitoring and optimal dose of enzyme replacement. Treatment of children with type 2 (most severe) neuropathic Gaucher disease is supportive. Pre-symptomatic children, usually with type 1 Gaucher, increasingly are being detected because of affected siblings and screening in high-prevalence communities. In this group, annual examinations (including bone density) are recommended. However, monitoring of asymptomatic children with affected siblings should be guided by the age and severity of manifestations in the first affected sibling. Treatment is necessary only if signs and symptoms develop. CONCLUSION: Early detection and treatment of symptomatic types 1 and 3 Gaucher disease with regular monitoring will optimize outcome. Pre-symptomatic children require regular monitoring. Genetic counseling is important.